Use static_cast rather than C-style cast

Editor assessment

The subject completely describes a cast-style modernization: C-style casts are replaced with static_cast. The motivation (type-checked, searchable, idiomatic C++) is inherent in the named construct, so no body is required, and none is present. The chore type fairly frames a mechanical hygiene sweep, no scope is needed for a cross-cutting replacement, and no footers appear. Hygiene is clean, with imperative phrasing and no trailing period. The message sets exact expectations for the diff and gives a reviewer no reason to distrust it. A complete small-change message.